Problem: $\int x^{-2}\,dx=$ $+C$
Explanation: The integrand is of the form $x^n$ where $n\neq-1$, so we can use the reverse power rule: $\int x^n\,dx=\dfrac{x^{n+1}}{n+1}+C$ $\begin{aligned} \int x^{{-2}}\,dx&=\dfrac{x^{{-2}+1}}{{-2}+1}+C \\\\ &=-x^{-1}+C \end{aligned}$ In conclusion, $\int x^{-2}\,dx=-x^{-1}+C$